{
  "source_id": "10.3176/phys.math.1973.4.19",
  "archive": "Estonian Academy Publishers archive (kirj.ee)",
  "publisher": "Estonian Academy Publishers",
  "journal": "Proceedings of the Academy of Sciences of the Estonian SSR. Physics. Mathematics",
  "journal_original": "Известия Академии наук Эстонской ССР. Физика. Математика",
  "year": 1973,
  "volume": "22",
  "issue": "4",
  "pages": "448–451",
  "first_page": 448,
  "last_page": 451,
  "title": "О ДВУХ ЭКСТРЕМАЛЬНЫХ ЗАДАЧАХ НА МНОЖЕСТВАХ ПРАДЕРЕВЬЕВ",
  "title_en": null,
  "authors": [
    "Tiit Riismaa"
  ],
  "language": "Russian",
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  "doi": "10.3176/phys.math.1973.4.19",
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  "license": "CC BY 4.0",
  "license_url": "http://creativecommons.org/licenses/by/4.0/",
  "license_evidence": "crossref license field (publisher policy page says CC BY-NC 4.0; see notes)",
  "license_notice": "Translated from Russian. Original: Tiit Riismaa, “О двух экстремальных задачах на множествах прадеревьев”, Proceedings of the Academy of Sciences of the Estonian SSR. Physics. Mathematics, 1973, vol. 22 no. 4, pp. 448–451, https://doi.org/10.3176/phys.math.1973.4.19. Published by Estonian Academy Publishers; license CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/) as deposited with Crossref by the publisher (the publisher's policy page names CC BY-NC 4.0). Changes: translated into English.",
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  "record_source": "harvested 2026-10-14 from the publisher's API"
}